lviii CHARLES OTIS WHITMAN 
Similarly, the instinct of capturing food exhibited perfectly 
by the youngest Necturus is innate. The pause before seizing 
the bait is part of a very old primitive mechanism found is fishes 
and finally developed into the ‘pointing’ of a dog. Its object 
is to fix the aim. The timidity of the young Necturus is also 
innate and not the result of painful experiences. 
‘““We have taken a very important step in our study when we 
have ascertained that behavior, which at first sight appeared to owe 
its purposive character to intelligence, cannot possibly be so 
explained, but must depend largely, at least, upon the mechanism 
of organization. The origin and meaning of the behavior ante- 
date all individual acquisitions and form part of the problem of 
the origin and history of the organization itself.” ‘‘We see 
at once that behavior does not stand for a simple and primary 
adaptation of a pre-existing mechanism to a special need. As the 
necessity for food did not arise for the first time in Necturus, 
the organization adapted to securing it must be traced back to 
foundations evolved long in advance of the species. The retro- 
spect stretches back to the origin of the vertebrate phylum . . 
The point of special emphasis here is that instincts 
are evolved, not improvised, and that their genealogy may be as 
complex and far-reaching as the history of their organic bases.” 
This passage should be read by all physiologists who, of all biol- 
ogists, are most given to neglecting phylogeny in their explana- 
tions. 
While instinct thus comes before intelligence and not after 
it, as many have believed, some intelligence was implied by the 
inhibition of instinctive acts in Necturus by fear. To clinch his 
argument that instincts are evolved like structures and are not 
inherited habits, he turns to two instincts cited by Romanes as 
clear evidence of their origin in habits; the tumbling and pouting 
of pigeons. An examination shows that the rudiments of these 
instincts are to be found in all species of pigeons. Again the value 
of the phyletic method of study is illustrated by the ‘brooding’ 
instinct of birds. This he shows to be the evolution of an instinct 
shown even in fishes, which hover over the nest and drive away 
